Luggage racks are extremely useful and popular accessory items for carrying a load on an exterior surface of an automotive vehicle. Typically such racks are mounted on the roof of the vehicle.
There are many prior art patents on luggage racks and article carriers. Early forms of such racks employing side rails with intermediate skid strips are shown in U.S. Pat. No. 26,538 and U.S. Pat. No. 26,539. More recent examples of racks of this general type are disclosed in U.S. Pat. Nos. 4,225,068, 4,239,138, 4,279,368 and 4,616,772.
Another general type of rack or carrier that has been used has slats along the sides of the vehicle on which stanchions connected to cross members are mounted. Examples of this type of rack are disclosed in U.S. Pat. Nos. 4,132,335, 4,244,501, 4,372,469, 4,406,386, 4,448,337, 4,469,261, 4,516,710 and 32,706.
In several recent designs, the cross members have stanchions which are slidably engaged with the side rails so that the cross members may be moved along the side rails to conform more or less to the size of the load and then locked in position by a pin type or other locking mechanism. Examples of this design are shown in U.S. Pat. Nos. 4,132,339, 4,406,386 and U.S. patent application Ser. No. 250,705. Additional patents of interest are U.S. Pat. Nos. 4,684,048 and 4,754,905.
There are forces acting on a loaded luggage rack when the vehicle is travelling at a high rate of speed, or during sudden braking or acceleration, that tend to separate the rack from the vehicle and the cross members from the rails. This is a serious problem for racks with movable cross members and pin type locking mechanisms.